I stay away from foods labeled as "diet" or "low Fat" as they tend to be worse for you than the real foods you are avoiding. For instance, processors don't make low-fat dairy products just by removing the fat. To restore the texture --- to make the drink "milky" --- they must add stuff, usually powdered milk. Did you know powdered milk contains oxidized cholesterol, said to be worse for your arteries than plain old cholesterol? And that removing the fat makes it harder for your body to absorb the fat-soluble vitamins that make milk a valuable food in the first place?
And so I eat "real" food. One good book on this subject is Michael Pollan's IN DEFENSE OF FOOD.
I eat Paleo or Primal style and have had great success with this. Basically, at least 70 to 80% of my meals consist of 4 to 8 OZ protein on a bed of leafy greens, with spinach being a favorite.
Breakfast is usually a mix of eggs and egg whites scrambled with chopped greens such as kale or spinach.
Trader Joe's sells these bags of mixed greens and I use this a lot in my eggs and other cooking
A couple of times a week I'll eat a cooked veggie such as squash or broccoli but raw greens are my favorite.
I eat very "clean" -- with all proteins being hormone-free, organic, free range, etc. All veggies are organic. I don't consume chemicals, sugar, grains, alcohol or excess salt. I have fats , fruit and dairy in moderation.
The weight falls off and cravings for the foods you shouldn't eat diminish over time and eventually disappear. Problems that I had with my skin disappeared and overall, my skin looks 20 years younger after only a few months of eating this way.
To read about this way of eating I recommend the book The Primal Blueprint: Reprogram your genes for effortless weight loss, vibrant health, and boundless energy by Mark Sisson.